Hudson camshaft profiles

Kdancy

Thought I'd give this it's own post for future reference---Hudson camshaft discussion—

A brief discussion of the
cams offered and what effect they have will be helpful in deciding which build
of 7X to aim for.

Standard factory cam for Hudson engines 232,262 and 308 is

 306344
lift is 356

Designated Super 7X cam introduced in fall of 53 was

311040 lift
390 duration 268 rough idle lopey exhaust note.

Designated 7X Flattop introduced in April of 54

 309742
lots of customer complaints about this cam. Trouble setting up and ate timing
chains. Was replaced later in 54 with the

306344A
series cam. I do not have lift and duration for these cams yet.

Clifford designated 1956 mechanical
grind cam which has a

lift of 376 and a duration
of 254

and is considered the
best cam choice as its super smooth and has power, nice to setup and none of
the roughness at idle of the other cams. With Twin H and 262 head will give you
176 hp with 7X engine relief and 7X valves around 185-200.

 HUDSON CAM HISTORY:

All Hudson engines come with the 306344 cam which became the standard low HP
cam for Hudson in 1953.

The 1954 Hudsons were delivered with the 309742 (7X) Flat Top cam and later in
1954 was replaced with the 306344A series cam.

The 311040 cam (Super 7X high lift cam (.390 gross lift) came out in the fall
of 1953 for all our Oval track racing and was listed as the severe use cam.

The HP rating of the 308 standard engines equipped with twin H power and the
7.5 to 1 CR head using a 306344 cam is 155HP.

When using the 309742 7x flat top cam the HP is 170 and when using the 311040
Super 7X cam the rating is 180HP.

 ivanz62
Expert Adviser

October 2013

A lot of bad info on this
topic of cams. All the stepdowns had pretty much the same cam

From 1948 to 1954 with the exception of the racing cams that were dealer or
owner installed.

344A in 1954 is very
little changed from 344 in all earlier Hornet engines.

The 742 and 040 cams were
for racing with the 040 replacing the "chain stretcher" 742 as the
choice in late 1953 or 1954.

In 1956 the 308 came with
hydraulic lifters and a somewhat higher performance cam--this gave 170 BHP with
Twin H and aluminum 7.5:1 compression head. Aftermarket cam grinders made a
solid lifter equivalent of this 1956 hydraulic grind.  Otherwise, use what you have if it is not
junk.

 

Kerry ,

I have looked at your info
supplied.  The cam print out for the
Hudson

#304078 (supposed to be
1950 only) agrees with what I have for the stock cam through 1954 regardless of
the number cast in the cam billet.  You
did not send the print out for the #309742 which could be many different
grinds.  I have seen that casting used
for a hydraulic lifter 1956 cam, the "Chain Stretcher" or "Flat
top" racing cam, and a standard 1955 grind essentially the same as your
#304078.

The three Crane grinds:

The Regrind 01139----This is more radical than the Isky full race cam used by most
Hudson racers for the last 50 years.

Crane                             Isky

106 degree                   110

.470" lift                       .446

.050"    258

Regrind   00984

This is very close to the
Isky full race cam       Crane

112                                  110

.450"                               .446

260 degree                     258

Regrind 01893

This would be a modest
performance boost from stock.  Same
lift--20 degrees more duration.  The
Clifford cam has another .020 lift and runs very sweetly in a street car.

Crane                             Clifford 56
mechanical equivalent

112                                    112

.350                                   .372

For performance I recommend the Hudson #311040
for the street without reservation unless you are just interested in fuel
economy.

110

.388" lift

233 degrees at .050 lift

Iskenderian has made a cam
close to this "040" Hudson that they called

"Hudson 6
Cyl"     "Grind: Full-44” This
was done about ten years ago.

113

.387"

232 degrees @ .050

Please send me the Crane
print of your #309742 cam so I can see it as well.

Hope this helps,

Ivan

  **** Anyone can send a Hudson camshaft to Crane Cams and they will re-grind it to the specs you want.

Geoff

On a similar note, I'm looking for a 8 cylinder camshaft 1934-52.  The one I have has over .055 worn off the nose of some of the cams, so not able to be re-profiled without building up which is an  expensive exercise.   Any help would be greatly appreciated.

Geoff